lucia's: Lookback: February Lookback - Mildest since 2002, Mar 09

Saturday, March 26, 2011

Lookback: February Lookback - Mildest since 2002, Mar 09 - 20:18

The first half of the month was strongly southwesterly and the zonality index across the Atlantic and Europe reached its highest since November 2009. There were heavy orographic rains, severe gales, and high temperatures between the 3rd and 7th. During the second half of the month blocking was prominent and persistent over eastern Europe, but cold southeasterlies only affected the UK between the 15th and 21st, and much of the country became exceptionally mild on the 24th and 25th.

Mean maximum temperature for February ranged from 10.9°C at St Mary's (Isles of Scilly) and Exeter airport (Devon) to 4.9°C at Dalwhinnie (Inverness-shire), while mean minimum temperature varied between 8.4°C at St Mary's and minus 0.1°C at Cromdale (Morayshire). Mean monthly temperatures were between 1 and 2 degC above the 1971-2000 average in Scotland and Northern Ireland, and between 2 and 3 degC above in most parts of England and Wales. The Central England Temperature (CET) of 6.6°C was 2.4°C above the long-term mean, the highest for February since 2002. In the last 100 years only eight Februarys were warmer by this measure.

The highest maximum at a standard site (i.e excluding rooftop and mountain sites) in the UK was 15.5°C at Writtle (Essex) on the 25th, while the lowest minimum was minus 6.5°C at Altnaharra (Sutherland) early on the 11th. The lowest daytime maximum was 0.7°C at Spadeadam (Cumbria) on the 19th, and the warmest night was that of the 4th/5th with a minimum of 12.2°C at Credenhill (Herefordshire).

Rainfall averaged over England and Wales during February was 84mm which is 132 per cent of the average for the standard reference period 1971-2000, the highest in February since 2007; in the last 100 years 28 Februarys were wetter while 72 were drier. The equivalent figures for Scotland were 116mm and 183 per cent of the normal amount, and for Northern Ireland 89mm and 155 per cent. Monthly totals at routinely-available sites ranged from 411mm at Capel Curig (Caernarfon) to 27mm at Cambridge.

Sunshine averaged over England and Wales during February was 50 hours which is 65 per cent of the 1971-2000 mean, the lowest since 1980; in the last 100 years only 11 Februarys were duller, while 89 were sunnier. The equivalent figures for Scotland were 61 hours and 84 per cent, and for Northern Ireland 78 hours and 104 per cent. Largest total in the UK was 75 hours at Kinloss (Morayshire) although Belmullet in the Irish Republic recorded 84 hours, and the smallest was just 32 hours at Wattisham (Suffolk) where it was the dullest February since sunshine was first recorded at the site in 1968.